The present invention concerns a system for detecting the end of useful life of a battery in an electronic timepiece having a stepping motor. Systems are already in existence in which the detection of the end of useful battery life is made by a measurement of the battery voltage and by a comparison thereof with a definite voltage level; when the battery voltage reaches this threshold, the watch indicates to the wearer that the batteries are at the end of their useful life.
However, such detection systems have the following disadvantages. On the one hand, if the defined voltage threshold for detecting the end of useful battery life is not close to the limit of the operation of the stepping motor, the watch may indicate to the wearer that the batteries are at the end of their useful life, whereas they could still be useful and insure good operation for several months. On the other hand, it is necessary to create the defined voltage threshold in the circuit which requires, according to present prior art, a resistor external to the integrated circuit, i.e., an extra component in the watch.